Coke oven battery with built-in gas ports



www H, 94@ A, Avg@ I 4 S COKE OVEN BATTERY WITH BUILT-IN GAS PORTS Filed Jun@ 12s, 1945 s sheets-sheet 1 Q ML:

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ATTORNE the iiues. In such vertical ue ovens,

Patented Nov. 15, 1949 COKE OVEN BATTERY WITH BUILT-IN GAS PORTS George A. Davis, Mountain Lakes, N. J..

toAllicd C poration of New York` Application June 13, 1945, Serial No. 599,189

3 Claims.

This invention relates to combination underjet regenerative coke oven batteries and more particularly to the design and construction of such batteries having completely integral, i. e. builtin," distribution systems for the distribution of air and lean gas to the individual ues of the heating walls.

In my Patent No. 2,334,612 of November 16, 1943, I have disclosed and claimed a regenerative coke oven battery, the regenerators of which are provided with inflow and outflow control ports which result in uniform distribution of the gaseous media flowing through the regenerators with consequent operation at maximum regenerative -emciency It is an object of this invention to provide a design of ports connecting the regenerators with the fiues which will result in the desired distribution of air and lean gas to the individual iiues of each heating wall, so that uniform and rapid coking of the coal charge in the coking chambers between the flued heating walls takes place.

Vertical heating yue coke oven batteries as heretofore built have ports in the base portions of the iues, which ports connect the fiues with the regenerators. The top portions of the vertical heating nues communicate through slide brickcontrolled ports with horizontal nues. The sizes of the ports in the base portions of the fiues and the setting of the slide brick controlling the ports in the horizontal fiues connecting the top portions of the vertical fiues control the iiow through l each coking chamber in horizontal cross-section is of tapered shape, the wide end of the coking chamber being on the coke side of the batery, i. e. the side the coke is discharged from the cokingvchamber, and

the narrower end on the pusher side. It will be understood that due to the taper of each coking chamber, the amount of coal in each unit of length of the coking chamber progressively increases from the narrower pusher end of the batteryto the Wider coke end thereof, requiring greater amounts of heat progressively along the length of the'coking chamber to obtain uniform coking.

For satisfactory coking, anon-uniform dis, tribution of air and lean gas to the individual ues of each heating wall is required. A gradual increase in ow of air and lean gas to the iiues of each heating wall from the pusher side to the coke side is required to compensate for the oven taper. Additional increases in iiow of air and leans gas to the end ues of each heating wall is required to compensate for radiation losses from the sides of the battery.

assignor hemical & Dye Corporation, a eor- It has been the practice in the past to accomplish air and lean gas distribution by the tedious trial and error adjustment of the slide brick controlling the ports in the horizontal nues connecting the top portions of the vertical ues. In some cases, six months or more of adjustments of the slide brick have been required to obtain the desired distribution of air and lean gas to the fiues. Frequently after a change in the operating schedule of the battery substantial readjustment of the slide brick has been found necessary. y

In connection with new coke oven batteries. it has been suggested to eiect regulation of the air and lean gas fed to the nues by adjusting the position of the slide brick prior to heating-up of the battery. However, this method, while resulting in far better distribution of air and lean gas than was ever achieved by the old trial and error adjustment method, was found objectionable in that many of the slide bricks were displaced by the operators when inserting thermocouples during the heating-up of the battery, thereby'disturbing the desired distribution of air and lean gas to the flues.

In accordance with this invention, air and lean gas regenerators are connected to the bases of the vertical fiues by ports of special construction and design, i. e. Venturi throat. having relatively high resistance to up ow land relatively low resistance to down now. The ports have the following construction features:

(1) The sides of each port diverge from the top" openings at an angle to the vertical of less than (2) The distance between (a) the point at which the air and the lean gas stream from the contiguous regenerators meet in the port. and (b) the top of the port, i. e. the point at which the mixed gas stream enters the heating flue, is not less than 10", and preferably not less than 13";

(3) The top opening of the port, i. e. the portion thereof entering the flue is rounded, the radius of' curvature of this rounded portion being not less than V2";

(4) The cross-sectional areas of the top openings of the ports of each heating wall are graduated in size so that the nue at the coke side of the battery has the port having the largest crosssectional area top opening, the ilue at the pusher side of the battery has the port having the next largest cross-sectional area top opening. and the top openings of the ports in the intermediate ilues of each heating Wall diifer in cross-sectional areas and are graduated to supply the desired amount 3 of air and leangas to each of the intermediate ilues.

In accordance with my invention:

(a) The sizes of the top openings of the ports regulate the flow of air and lean gas to the `ilues during the upilow; the sizes of the top openings are chosen to give the desired air and lean gas distribution to the nues during upnow.

the coking chamber and the tops of the regenerators, in which are disposed the ports connecting the regenerators with the flues; A

Fig. 4 is a fragmentary plan view showing the ports in the base of the nues of a heating wall; and

Fig. 5 is an enlarged sectional view showing in `full lines the port connection between a pair'of (b) The ports permit the passage of waste gases during the downiiow to the regenerators with minimum pressure loss. This is due chiefly to the rounded or curved top openings of the ports and the gradual slope of the sides.

(c) Each port regulates the sum of the now of air and lean gas to the vertical heating flue in which it is positioned. Since the division wall in each port extends to a, point such that air and lean gas meet 'at -a distance not less than 10", and preferably not less than 13", below the point at which they enter the flue, it establishes sufncient restriction between the air side and the lean g-as side of the port to control the air to lean gas ratio. Thus, by controlling the sum of air and lean gas entering each` flue `and ratio of air to gas, the flow of each medium is controlled.

(d) By having a radius of curvature of the contiguous regenerators and the vertical heating flue on the coke 'side of the battery and showing in dotted lines the ports leading into other nues of a heating wall.

Referring to the drawings, the coke oven battery structure illustrated in Figs. 1 and 2 comprises a deck or oven base I which extends for the full length and width of and supports the battery brickwork. In the upper portions of this brickwork lare transversely-extending coking rounded portion of the top openings not less than a half inch, downow resistance is minimized. Furthermore, if this radius of curvature is substantially less than -a half inch accurate control of flow is impossible. It is well known that the orifice coefficient of a port (which is the measure of flow through the port at a given pressure dif ference) is influenced by the corner radius at the port entrance. ing a corner radius less than a half inch, slight but unpredictable crumbling of the edges has the effect of changing the corner radius with substantial eiect on the orifice coecient. However, when the corner radius is a half inch or more, variations in the corner radius, it has been found, have inconsequential effect on the orifice coefficient.

(e) By graduating the cross-sectional areas of the top openings of the ports of each heating wall so that the port having the top opening of the greatest cross-sectional area is in the coke side flue and the port having the next largest crosssectional area is in the pusher side flue and the top openings of the ports in .the remaining nues are of different cross-sectional areas, all the ports being so dimensioned -as to provide the desired amount of air and lean gas to each nue to compensate for oven taper and radiation losses, the desired -distribution of air and lean gas to .the

flues of each heating wall to effect uniform and rapid coking of the coal charge is effected.

In the accompanying drawings forming a part of this specification and showing for purposes of exemplication apreferred embodiment of the invention but without limiting the invention to this embodiment:

In the case of a brick port havchambers 2 land heating Walls 3 alternating with the coking chambers. In the lower portion of this oven battery structure are transversely-extending regenerator rows, regenerators of row 4 serving Ato preheat air and the regenerators of row 5 serving to preheat lean gas, such as producer or blast furnace gas. Each row erregenerators 4, 5 is constituted of a middle section 6 and outer sections 1 and 8. Regenerator sole channels or passages 9 extend into the `oven brickwork from one side of the battery; air or lean gas is supplied to and products of combustion withdrawn from the bottom of the regenerators through these sole channels.

The deck member I is ordinarily formed of reinforced concrete and may be a single slab, although preferably it is divided into a plurality of longitudinal sections separated by expansion joints, as disclosed in Patent No. 2,088,532, granted July 27, 1937. The deck member I is supported mainly by a multiplicity of vertical columns I0, which may be of reinforced concrete. These columns are disposed longitudinally of the battery, preferably beneath alternating regenerators disposed lengthwise of the battery, as shown in Fig. 2, and also crosswise of the battery. Masonry walls II and I2 are disposed at the sides of the battery. Suitable angle irons or masonry closures may be provided between these walls and deck I so that the joints therebetween are closed against Fig. 1 is a composite vertical section taken crosswise to the battery, the left hand portion being taken through 'a heating wall, which in the interests of clarity is shown in full lines, and the right hand portion being taken through a coking chamber, of a coke oven battery embodying the present invention;

Fig. 2 is a fragmentary vertical section taken lengthwise of the battery and along line 2-2 of Fig. 1;

Fig. 3 is a fragmentary vertical section on a larger scale showing details of the `brickwork in the portions of the battery defining the Walls of the entrance of air into the basement space I3. Conventional .pinion walls, not shown, are provided at the ends of the battery for additionally supporting the deck member and for retaining in place the ends of the brickwork supported on the-deck member.

Chimney flue III is located Ion the pusher side of the battery, runs the full length thereof, and is disposed so that its top I5 is substantially at a level with the top of the basement space I3 and its bottom is defined by masonry which is integral With the masonry foundation for the oven battery. It is communicably connected with the regenerators as hereinafter more fully described. Located at the same side of the battery as the chimney flue are reversing valves I6, which may take various forms and which collectively provide for the discharge of waste heat gases from the regenerators through the sole channels 9 to the chimney flue I4 and for the supply of air and lean gas to the regenerators. Air is supplied to the air regenerators through passageways II communicably connecting the basement space I3 with the sole iiues 9. In' the structure shown on Fig. 1, a valve I8 controls the now of air from the basement space I3 through'the Apassageway I1 into the sole channel 9 of each regenerator 6 of regenerators of row 4. This valve is shown in open position in Fig. 1 because the Iair regenerators 'I and 8 with which the sole channel 9 communicates are operative for inflow of air. A valve I9 is provided for controlling the flow of products of combustion from each sole channel 9 communicating with the `regenerators. This valve is shown in closed position in Fig. 1 because the end regenerators are shown operative for inflow of air. A butterfly valve 20 is positioned in the passageway 2| connecting each sole channel 9 with the chimney flue I4, which buttery valve may be suitably positioned by the operator to obtain the desired stack draft causing flow of products of combustion into the chimney flue.

It will be understood that valves similar to I8, I9 are provided for the sole channels communieating with the air regenerators 6, which valves control the 4flow of air into regenerators 6 from the basement space and the outflow of products of combustion from these regenerators into chimney flue I4. Thus, when the valves I8 controlling the flow of air into the middle regenerators 6 along the length of the battery are closed, the corresponding valves controlling the flow of air into the regenerators 'I and 8 are open. Likewise. when the valves I9 controlling the now of products of combustion from the middle regenerators 6 into the chimney ue are open, the corresponding valves in the passageway/s connecting the sole channels to the regenerators 1 and 8 with the chimney flue are closed. Each passageway connecting the basement space with a sole channel may be provided with a port that may be throttled by removable and replaceable iinger bars.

A lean gas main 22 is provided in the basement space I3 and communicates with the sole channels of the regenerators of row to alternately supply lean gas to the middle regenerators of row 5 and upon interruption of gas flow to the middle regenerators then to the end regenerators 'I and 8 of row5; ow of gas being controlled by valves operated by the automatic reversal mechanism. The valve mechanism for controlling gas flow to the gas regenerators and outflow of products of combustion therefrom is well known and, in general, is similar to that hereinabove described, and no useful purpose wouldbe served by disclosing it in greater detail.

When operating with fuel gas, such as coke oven gas, fed directly to the ues, all the inflow regenerators are preferably used to preheat the air fed to the ues.

' Each coking chamber 2 is preferably provided with a plurality of charging holes 23, and with the usual valve-controlled gas oitake communieating with the collector main system. The ends of the coking chambers, as conventional, are adapted to be closed by removable doors which may be of the self-sealing type.

The heating walls 3 are formed with vertical heating flues having in alternate ues high and low burners 24, 25, respectively, and access :flues 25' which permit observation of the combustion conditions within the flues. In the embodiment of the invention shown in Fig. 1, each heating wall on the pusher side has a concurrently operable group of eight flues, identified by the reference characters 26-33, respectively, communieating through a horizontal flue 34 with an interior group of eight flues, 35-42. On the coke side of the battery the vertical ues are connected by horizontal flue 43 into two unequal groups of concurrently operable flues, the interior group of seven iues being identified by the reference characters 44-50 and the outer group of six flues by the' reference characters 5I56. Thus, in the embodiment of the invention shown in Fig. 1, the iiues of each heating wall are operatively disposed in two outer and two inner groups of concurrently operable flues, the flues of each group operating concurrently for flow in the same direction. During one period of operation flues 26-33 and 5I-56 of the outer groups operate concurrently as inflow flues, as indicated by the arrows in Fig. 1, receiving air and lean gas from theregenerators 'I and 8, while the inner groups of iiues 35-42, 44-50 operate concurrently as outflow flues, the products of combustion owing into the rcgenerators 6 of rows 4 and 5, as is also indicated by the arrows on Fig. l. Upon reversal,

the inner groups of flues of each heating wall operate as iniiow flues, while the outer groups of iiues operate concurrently as ouflow flues.

Referring to Figs. 2 and 3, it will be noted the air and lean gas regenerators'are arranged in pairs, each pair communicating through a common port with a heating flue in the heating wall thereabove. One of these ports is shown on enlarged scale in Fig. 5 and consists of a throatA portion defined by side walls 59 and two branches 6I, 62 hereinafter more fully described. Referring to this figure, it will be noted the port comprises a top opening 57, the walls of which are rounded or curved, as indicated by reference character 58, the radius of curvature being not less than l. This top opening may be of rectangular or other desired shape; it is important, however, that no sharp corners be formed where the port enters the flue and 'that the walls dening the top opening be rounded, as hereinabove set forth.

The side walls of the port leading from the top opening are identied by reference character 59.

The division or pillar wall 60 separating the air and lean gas regenerators extends to a point not less than 10 and preferably not less than 13 below the point at which the port communicates with the base of the flue. Thus there are formed branches 6I, 62 which extend from the base of side walls 59 and gradually diverge and open into the air and lean gas regenerators. The walls of the diverging. branches where they enter the regenerators are rounded, as indicated by reference characters 63, 64, respectively.

As shown in Fig. 3, in the construction of the side walls 59 of the ports, two courses of brick are employed, the top course being approximately 81/8 thick and the course beneath 51A'l thick, so that the total length of side walls 59 is 13S/8. The use of two courses of brick as shown permits the use of brick of standard thickness; the brick is, of course, modified to form ports having the desired angle of divergence of the side walls and to provide the rounded walls 58.

As indicated above, it is important that the angle of 4divergence i. e. the angle between the side walls of the port and the vertical, not exceed 10. In the preferred embodiment shown on the drawing', as shown in full lines in Fig. 5, the side walls of the port in the coke side ilue 56 are vertical i. e. have an angle of divergence of 0. The side walls of the ports in the remaining flues of each heating wall are inclined. From Fig. 5 which is a composite View showing the relative sizes of a number of ports in the flues of a heating wall it will be noted that in effect the side walls of the ports extend from a so called pivot point 59' to the top openings, certain oi the ports having greater angles of divergence than others, all, however, being less than 10, thereby resulting in the formation of top openings 51 of different widths and hence of different cross sectional areas to compensate for oven taper. In Fig. 5 dotted line 55a represents the side walls of the port in flue 55, 52a the side walls of the port in flue 52, 38a the side walls of the port in flue 38, and 36a the side walls of the port in flue 3I. The relative sizes of the top openings 51 of a number of the ports in the ues of a heating wall is shown in Fig. 4 of the drawings.

The preferred dimensions for the ports in the flues of a heating wall having four groups of ues therein, as shown in the drawings, are given in the following table:

The length and width dimensions are for the length and width, respectively, of the top opening of the port 51. As disclosed above, the depth of the wall portion 59 of the port should be at least 10 and preferably at least 13".

Cross- Angle of Fluo Length Width sectional diver- Area gence Inches Inches Sq. in Degrees als 7% 25. s 2. 5 25,5 6% 15. 6 5.0 21/2 5 12. 5 7. 7 21%; 4% ll. 9 8. 2 2V; 41,( 1l. 9 8. 2 2 1 4% ll. 2 8. 8 21.12 4% l0y 6 9. 3 2,12 4 l0. 0 i). 8 2%; 4% l0. 6 9. 3 2]@ 4% i1. 2 s. 8 2,1 4% l1. 9 8. 2 215 5 l2. 5 7. 7 21.2 51e; 13. 7 6. 6 21@ 5,12' 13. 7 6. 6 21') n l5. 0 5. 5 212' 6 ,15. 0 5. 5 21,2 6% 16. 6 4. 2 2,1/2 6512 16. 6 4. 2 21/' 6% 16. 6 4. 2 2/2 6% 15. e 5. 0 2,1 i 6 15. 0 5. 5 2h 5% 13. 7 6. 6 2j 5% 13. 1 1. 1 21 g 5% 13. 7 6. 6 2,1/2' (i l5. 0 5. 5 2,' -g 0% 1s. 6 4. 2 21.2' 731/2 1s. 7 2. 2 315 'I1/ 24. 9 3. 0 S 5 8% 33.0 0

It will be noted from the above table the crosssectional areas of the top openings of the ports in the group of ilues on the pusher side of the battery decrease from a maximum of 25.8 square inches for the top opening of the port on the pusher side to l square inches for the crosssectional area of the top opening 51 of the port in flue 33. It will be further noted that the crosssectional areas of the top openings 51 of the ports in the interior groups of flues 35-42, inclusive, gradually increase in cross-sectional area from 10.6 square inches for the top opening 51 of the port in flue 35 to a cross-sectional area of 15 square inches for the top opening 51 of the port in flue 42. The cross-sectional areas of the top openings 51 of the ports in the group of ues 44-50. inclusive, decrease from the pusher to the coke side of the battery from 16.6 square inches for the top opening 51 of the port in flue 44 to 13.1 square inches for the top opening 51 of the port in flue 50. The cross-sectional areas of the top openings 51 of the ports in ues 5I-56, inclusive, gradually increase from a cross-sectional area of 13.7 square inches for the top opening 51 of the port in ue I to 33 square inches cross-sectional area for the top opening 51 of the port in flue 56.

The dimensioning of the ports. as hereinabove disclosed. takes into account static pressure var- 8 iations along each of the horizontal ues 3l, results in the desired control of flow of air and lean gas to the vertical heating nues during the upow, so that there takes place the necessary increased flow of both air and lean gas to the end flues on the coke and pusher side of the battery to compensate for radiation losses and also the necessary increased ow of air and lean gas to the interior ues on the coke side of the battery, as compared to the interior ues on the pusher side of the battery, to compensate for the oven taper.

Each ilue receives fuel gas, such as coke oven gas, through an individual uprising channel 65 extending through deck I and connected at its lower end with one of a pair of gas distribution mains 66, 61 (Fig. 2) disposed in the basement space I3 near the top thereof crosswise of the battery. As appears from Fig. 2, these crosswiseextending means 66, 61 are positioned beneath the heating walls 3. Each main 61 is provided with individual uprising channels 65 communieating only with the interior groups of ues in a heating wall thereabove. Each main 66 is provided With individual uprising channels 65 communicating only with the exterior groups of flues in a heating wall thereabove. l

Each uprising channel 65, at the point where it is connected with main 66 or 61, as the case may be, is provided with a ow regulator (not shown) for controlling the flow of gas supplied to the flue. This flow regulator preferably is of the type described and claimed in Patent No. 2,199,961 of May 7. 1940. These regulating devices require attention and occasional adjustment by an attendant working in the basement space.

Each main 66, 61 communicates with a fuel gas supply main 10 (Fig. 1) connected therewith by means of piping 1I. Main 10 is suitably insulated against loss of heat. Piping 1I is provided with a three-way valve 'I2 and a shut-off valve 13 which is normally open, but may, if desired, be closed to prevent flow of gas from main 10 to the crossover mains 66, 61. Leading into the three-way valve I2 is flexible pipe 14, which communicates with a decarbonizing air main 15 suitably supported in the basement space I3. Operation of the three-way valve 12 by usual automatic reversal mechanism functions to place the main 10 into communication with either main 66 or 61 and to place the decarbonizing air main 15 into communication with these mains 66, 61 when fuel gas is not being supplied thereto. Upon reversal of operation the three-way valve 12 is operated to place decarbonizing air main 15 in communication with the crossmains 66 or 61, to which previously fuel gas had been supplied in accordance with customary procedure of supplying fuel gas and decarbonizing air to the gas distribution systems of coke oven batteries.

Located at the coke side of the battery is an air channel or passageway 16 running the full length of the battery to which air may be supplied through one or both ends thereof. If desired, a fan or blower (not shown) may be disposed at one end of the air channel 16 with its outlet arranged to blow the air at any desired pressure, say about 1/ pound above atmospheric, to the channel 16. The air admitted to the channel may be passed through a filter cloth or other air conditioner, so that clean air of predetermined humidity is admitted to the channel and flows therefrom through openings 11 into the basement space I3 and from this vspace into the regenera- In operation, when the exterior groups of ues 26-33. and 5I-56, both inclusive, operate for inilow, due to the proportioning of the ports, as hereinabove disclosed, the volume of air and lean gas gradually increases from flue to ue (excepting the end iiues 26, 56) in a direction running from the pusher to the coke side of the battery, the greatest volume of air and lean gas being admitted to the coke side ue 56. In the exterior group of ues 26-33, inclusive, which operates for inow concurrently with ues `'uh-56, the greatest volume of air and lean gas is admitted to ue 26 on the pusher side of the battery. The cross-sectional areas of the top openings of the ports hereinabove given, taking into account the static pressure variations along horizontal flue 34, result in the admission of a volume of air and lean gas mixture to the flues 21-33 which gradually increases running from the pusher to the coke side of the battery. The products of combustion formed flow into the groups of flues 35-42 and 44-50, respectively; thence to the regenerators 6 into the chimney flue I4.

Upon reversal, air and lean gas are admitted to the ues of groups 35-42 and 44-50. The crosssectional areas of the top openings of the ports in the iiues, taking into account static pressure variations along horizontal flue 43, result in gradually increasing volumes of air and lean gas to be admitted to the fiues 35-50, running from the pusher to the coke side of the battery, the products of combustion formed leaving through lues 26-33 and 5I-58 and flowing into regenerators 1, 8 and thence to the chimney ue I4.

It will be noted that, except for the end ues 26, 56 there is a gradual increase in the volumes of air and lean gas admitted to the rlues of each heating wall from the pusher to the coke side, thereby compensating for oven taper; Further still larger volumes of air and lean gas are admitted to the flues 26, 58 than to the remaining dues thereby compensating for radiation losses. The hereinabove described arrangement of ports results in remarkably uniform and rapid coking of the coal charge.

It will be noted in the coke oven of this invention, the distribution system for distribution of air and lean gas to the individual ues of each heating wall is completely integral, i. e. built-in, and that no slide brick or other adjusting means is required to obtain the desired distribution.

While a preferred embodiment of my invention has been shown and described, it will be apparent to those skilled in the art that changes may be made without departing from the invention as set forth in the appended claims.

I claim:

1. A regenerative coke oven battery constituted of heating walls and coking chambers arranged side by side, each heating wall containing vertical iiues arranged in two outer groups of concurrently operable flues and two inner groups of concurrently operable iiues, the outer groups of fiues being communicably connected to the inner groups of flues for upow through the outergroups of flues and downflow through the inner groups of ues, and upon reversal, uplow through the inner groups of flues and downflow through the outer groups of ues, crosswise extending regenerators disposed beneath the coking chambers arranged withv a row of air regnerators alternating with a row of lean gas regenerators lengthwise of the battery, means for supplying air to the regenerators, a compound port in the base of each heating iiue connecting said flue with an air and lean gas regenerator, said port being constructed and arranged so that the distance between the point at which vthe air and lean gas streams meet in said port and the point at which the resultant air and gas mixture enters the ue is not less than 10", n? walls of said port having an angle of diverge ce not greater than 10, the walls defining the top opening of the port entering said iiue being rounded and the radius of curvature of said rounded portion being not less than 1/2" and the cross-sectional areas of the top openings of said ports in the lues of each heating wall being graduated so that the cross-sectional areas of the top openings of the ports in the outer group of ues on the pusher side of the battery gradually decrease from the pusher to the coke side of the battery, the cross-sectional areas of the top openings of the ports in the inner group of ues on the pusher side of the battery gradually increase from the pusher to the coke side of the battery, the cross-sectional areas of the top openings of the ports in the next group of flues gradually decrease from the pusher to the coke side of the battery and the cross-sectional areas of the top openings of the ports in the group of ues on the coke side of the battery gradually increase from the pusher to the coke side of the battery, the top opening of the port in the flue on the coke side of the battery having the largest cross-sectional area, and the top opening of the port in the fiue on the pusher side of the battery having the lnext largest cross-sectional area.

2. A regenerative coke oven battery comprising vertically ued heating walls alternating with horizontally extending tapered coking chambers, crosswise extending air and lean gas regenerators disposed beneath the coking chambers, a series of compound built in ports connecting the crosswise extending air and lean gas regenerators with the fiues of a heating wall thereabove, each of vsaid ports being constructed and arranged so that the distance between the point at which the air and gas enter the port and the top opening in the port is not less than 10", side walls of the port diverge from the top opening o f said port at an angle of divergence of not greater than 10 and the walls defining the top opening of said port are rounded, the radiusv of curvature of said rounded portion being not less than a half inch, the angle of divergence of the side walls of the port in the coke side flue being smallest, the top port opening in said coke side/flue being of maximum cross sectional area, the angle of divergence of the side l walls of the port in the pusher side ue being next smallest, the top port opening in said pusher side ue being of the next largest cross sectional area thereby compensating for radiation losses and,

and result in uniform heating of the coking UNITED STATES PATENTS chamber.

3. A coke oven battery as deined in claim 2, Nluggeaz Wrilgne septnzaelgm in which the distance between the point at which 2100762 Becker "f Nov' 30 1937 the air and gas enter each port and thetop open- 5 2107'642 Mcmtir Feb 8 1938 mg m said port s not less than 13 2,132,522 Vri Ackeren oct. 11, 1938 2,186,237 Denig Jan. 9, 1940 GEORGE A' DAVIS' 2,334,612 Davis N0v.16,1943

REFERENCES CITED 10 FOREIGN PATENTS The following references are of record 1n the Number Country Date le of this patent: 484,737

Australia. Oct. 19, 1929 

